http://www.straightdope.com/classics/a3_023a.html
There are no practical reasons. Putting buttons on different
sides make sure that your shirt is either “man’s shirt” or
a “woman’s shirt”. This is important for religious reasons:
Deuteronomy 22,5 ""A woman shall not wear man’s clothing, nor shall a man put on a woman’s clothing; for whoever does these things is an abomination to the LORD your God.
One of the “crimes” of Joan of Arc (burned in 1431)was wearing men’s clothes.
I’ve heard that it’s also a holdover from the days when women were dressed by their maids, but this doesn’t account for the fact that men got dressed by their dressers, too…
It’s so that a couple can peek into each others shirt when they are sitting down (as long as the male is on the left hand side and the female is on the right hand side).
I’ve heard two explanations for men’s shirts and jackets to button left over right.
First, so the skirt of the coat will not interfere with drawing a sword carried on the left hip.
Second, so that the skirt will not get in the way when mounting a horse. This second reason makes no sense to me. The left foot goes in the stirrup and the right leg swings over. How things button shouldn’t make any difference. You mount from the left side because your sword is hanging off that side.
Men’s shirts buttonon the left so that you can button your shirt with your left hand, keeping your right hand free to wield your weapon of choice.
At least that’s what I’ve always heard.
My guess for why women’s shirts are the other way: How about for breastfeeding?
May I quote from the original column,
Cecil wrote:
“According to legend, women button right
over left because in medieval times they were dressed by their right-handed maids. Don’t buy it? Can’t say as I blame
you, but the alternative explanation is no improvement: men had to keep their right hand tucked into their coats so as
to be ready for cold-weather swordplay, whereas women always breastfed with the left breast (hey, that’s what it
says here) and protected their babies by covering them with the right side of the dress or coat.”
It seem that everybody is agreeing with Cecil.
What about the religious angle?
(My original post)
Just to reinforce Cecil’s claim that the other explanation is silly: Wouldn’t a woman who nursed using one breast exclusively be in an awful lot of pain? I’m not speaking from personal experience, of course, but I’ve heard.
The religious argument does sound plausible, but is there any evidence that that was the actual reason?
An interesting point is that Orthodox Jews use the opposite convention.
Oh no! I’m an abomination to the Lord God. I wear men’s t-shirts, and nothing fits better than a nice worn pair of men’s 501s.
I learned this from my anatomy teacher, so I don’t know how credible it is.
She said that men, when walking with a lady, are always supposed to walk on the part of the sidewalk closer to the street. If they walk in the correct direction on the sidewalk (man on the right), the man would not be able to peek into the gaps between the buttons on the woman’s shirt.
Before that, I was always told that it was because the women got fastened up by their maids.
Cute theory, but there are two problems. First, the man-walks-on-the-outside rule is not at all universal; other countries specify inside, right, and left. Second, the rule applies to sidewalks, and it is possible to walk on the sidewalk on either side of the street.
Moreover, women rarely wore button fronts, and never wore them without some kind of undergarment before the late 1960’s. It’s coats you have to look at to find the origin.
Breast-feeding is right out as a factor. The social classes that wore buttoned clothing didn’t breast feed.
The most believable theory I have heard is that everyone started out with the right over the left, but men changed for right-handed sword access. (This one, for a change, actually holds out some hope of being testable.)
I have it on good authority that the explanation is as follows:
It’s a holdover from the development of armor.
In the 14th century, the newfangled crossbows were able to penetrate chainmail armor, so brigandine (metal plates sewn or riveted onto a surcoat) was developed. One fought with the left side (the side with the shield) facing one’s opponent, so the coat had to be buckled left-side over right to deflect incoming sword/spear points.
Hmm, that explains why men’s coats go left over right,but not why women’s are the other way around…
I have never seen a surcoat that did not simply go over the head.
I rather fancy the period that has to be examined extends from the Restoration to the death of Prince Albert.
JWK,
“Surcoat” in it’s most technical sense refers to the long outer cloth covering worn over armor, and it’s true that they went over the head. I was using (possibly incorrectly,I’ll admit) in the looser sense of simply a coat worn on the outside of other clothing/gear. In any case, a brigandine coat did indeed use buckles. I found a picture for you:
http://www.soshs-armory.com/geoffrey/pictures/brigfrnt.html
Wearing each others clothing is an abomniation of “Man” and not God. I am sure the Church with all their hateful insanity during those times made up a lot of silly hateful and paranoid rules, then shoved them all down the people’s throats to make them feel ashamed of yet more stuff. 
Next time, before being so “sure” of anything, you might want to check your facts instead of making them up. It is, of course, to be found in the Torah.